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Submission #900441

# Submission time Handle Problem Language Result Execution time Memory
900441 2024-01-08T10:06:03 Z abcvuitunggio Islands (IOI08_islands) C++17
100 / 100
 204 ms 29776 KB 
#include <bits/stdc++.h>
using namespace std;
const int mxn=1000001;
const long long INF=1e18;
queue <int> q;
int n,p[mxn],l[mxn],last[mxn],x,u;
bitset <mxn> ch;
long long dp[mxn],d[mxn],val,res,a,b,sum,s;
int main(){
    ios_base::sync_with_stdio(NULL);cin.tie(nullptr);
    cin >> n;
    for (int i=1;i<=n;i++){
        cin >> p[i] >> l[i];
        last[p[i]]++;
    }
    for (int i=1;i<=n;i++)
        if (!last[i])
            q.push(i);
    while (!q.empty()){
        u=q.front();
        q.pop();
        ch[u]=1;
        d[p[u]]=max(max(d[p[u]],d[u]),dp[p[u]]+dp[u]+l[u]);
        dp[p[u]]=max(dp[p[u]],dp[u]+l[u]);
        if (!--last[p[u]])
            q.push(p[u]);
    }
    memset(last,0,sizeof(last));
    for (int i=1;i<=n;i++){
        if (ch[i])
            continue;
        sum=0,a=b=-INF;
        x=i;
        while (true){
            sum+=l[x];
            ch[x]=1;
            last[p[x]]=x;
            x=p[x];
            if (x==i)
                break;
        }
        val=0,s=sum;
        for (x=last[i];;x=last[x]){
            val=max(max(val,d[x]),dp[x]+max(a-s,b+sum+s));
            a=max(a,dp[x]+s);
            b=max(b,dp[x]-s);
            s-=l[last[x]];
            if (x==i)
                break;
        }
        res+=val;
    }
    cout << res;
}

Subtask #1
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 8540 KB Output is correct
2 Correct 2 ms 8540 KB Output is correct
3 Correct 1 ms 8540 KB Output is correct
4 Correct 1 ms 8540 KB Output is correct
5 Correct 1 ms 8540 KB Output is correct
6 Correct 1 ms 8540 KB Output is correct
7 Correct 1 ms 8792 KB Output is correct
8 Correct 1 ms 8540 KB Output is correct
9 Correct 1 ms 8540 KB Output is correct
10 Correct 1 ms 8540 KB Output is correct
11 Correct 2 ms 8536 KB Output is correct

Subtask #2
3.0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 8540 KB Output is correct
2 Correct 1 ms 8540 KB Output is correct

Subtask #3
4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 8540 KB Output is correct
2 Correct 2 ms 8540 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 8796 KB Output is correct
2 Correct 6 ms 9308 KB Output is correct
3 Correct 4 ms 8796 KB Output is correct
4 Correct 3 ms 8792 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 9564 KB Output is correct
2 Correct 14 ms 9948 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 29 ms 12124 KB Output is correct
2 Correct 34 ms 9940 KB Output is correct
3 Correct 37 ms 12760 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 54 ms 18260 KB Output is correct
2 Correct 73 ms 21588 KB Output is correct
3 Correct 67 ms 14048 KB Output is correct
4 Correct 101 ms 23756 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 142 ms 16584 KB Output is correct
2 Correct 146 ms 23124 KB Output is correct
3 Correct 107 ms 25428 KB Output is correct
4 Correct 145 ms 29640 KB Output is correct
5 Correct 138 ms 29776 KB Output is correct
6 Correct 195 ms 28980 KB Output is correct
7 Correct 151 ms 29400 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 138 ms 27856 KB Output is correct
2 Correct 148 ms 27732 KB Output is correct
3 Correct 133 ms 13276 KB Output is correct
4 Correct 130 ms 13392 KB Output is correct
5 Correct 135 ms 29140 KB Output is correct
6 Correct 136 ms 29144 KB Output is correct
7 Correct 204 ms 29136 KB Output is correct